Timothy Kurek, 26, of Nashville, decided in 2009 to go “undercover” as a gay man to better understand how society responds to gay individuals. A devout Christian man, Kurek lived the majority of his young life believing that homosexuality was a sin. It was not until a friend of his revealed to him that she had come out as a lesbian and that her parents had disowned her when she came out.

Kurek said that as she was confiding in him, he could only think of how he could “convert” her. It was at that point that he decided he needed to change his thinking, he profiles in his book “The Cross in the Closet.” Book sales are being launched on Thursday, which is National Coming Out Day.

For a year, Kurek “came out” to his friends and family—with everyone, except for three select people, thinking that he is now gay. With the help of his gay friend that acted as his “pretend boyfriend,” Kurek was convincingly living as a gay man.

"The thing that struck me most was the isolation," Kurek said. "Before I came out as gay, I had a very busy social life. After I came out, I didn't hear from 95 percent of my friends," he said, according to ABC News.

The experiment aimed to humanize the issue of breaking down homophobia, Kurek said.